电解浸出废旧锂电池中钴的热力学和动力学  

Thermodynamic and kinetic of electrolytic leaching cobalt from waste lithium-ion battery

作　　者：张建[1,2] 满瑞林[1,2] 徐筱群[1,2] 贺凤[1,2] 吴奇[1,2] 尹晓莹[1,2] 

机构地区：[1]中南大学化学化工学院,长沙410083 [2]中南大学有色金属资源化学教育部重点实验室,长沙410083

出　　处：《中国有色金属学报》2014年第4期993-1000,共8页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(21046007)

摘　　要：以废旧锂电池正极条为阴极，以铅板作阳极，在稀硫酸溶液中，电解浸出正极材料中的钴，从热力学和动力学两方面对钴的电解浸出过程进行研究。实验及热力学数据分析表明：LiCoO 2主要通过Co（OH）3还原浸出得到Co2＋，考查浸出温度和时间表明在电解前期5~30 min电解浸出由缩核模型的化学反应过程控制，浸出率α与时间t满足未反应核收缩模型1-（1-α）1/3=Kt，其表观活化能为7.32 kJ/mol；中期是混合控制；后期75~180 min符合内扩散控制模型1-2α/3-（1-α）2/3=Kt，表观活化能17.05 kJ/mol。浸出液中的铝主要是铝箔表面氧化铝层不受阴极保护而溶于硫酸溶液，正极材料从铝箔上剥离与氧化铝层的溶解有关，剥离时间影响钴的浸出率。Cobalt in spent lithium-ion battery was leached out in sulfuric acid using the cathode bar as cathode and lead plate as anode. And the process was studied in thermodynamics and dynamics two aspects. The results show that LiCoO 2 is reductive leached Co2＋by Co（OH）3through compared experiments and thermodynamic data. Through theoretical analysis and experimental research, the process is controlled by chemical reaction process of shrinking core model in the early 5-30 min, leaching rateα and timet satisfy inner diffusion the unreacted core shrinking model equation 1-（1-α）1/3=Kt, apparent activation energy is 7.32 kJ/mol. The middle stage is hybrid control. And the last conforms with the internal diffusion model, whereα andt suit to 1-2α/3-（1-α）2/3=Kt, and the apparent activation energy is 17.05 kJ/mol. Al3＋ in leach solutions comes from aluminium oxide dissolved in liquid without protection. The cathode material peeled from aluminum foil is related to the dissolution of aluminium oxide, which affects the leaching rate of cobalt.

关 键 词：废旧锂电池 电解浸出 热力学 动力学 

分 类 号：TM912.9[电气工程—电力电子与电力传动]